Hey RealM, as @wjs018@lemmy.ml has already suggested, this is a kbin quirk. It's documented on the kbin Codeberg bug tracker as #350. The kbin maintainers have not yet commented on whether this is intended behavior or a bug, but it does not appear as if anything will be done about the problem in the near future.

The only course of action that I could possibly take to work around the issue is to remove the bot flag from @shinobu@ani.social. Unfortunately, doing this would violate the right of Lemmy users to opt out of seeing bot activity -- not to mention also violate the ToS of numerous instances (including ani.social)

If I remember correctly, kbin doesn't allow bot accounts to federate by default. I don't know if there are manual exceptions that can be made or not.

As a fellow Kbin user, I ended up creating a lemmy account just for this and making it my anime account instead. It's a little annoying to have multiple accounts, but also its good redundancy in case something happens to one of them.